OBJECTIVE To confirm membrane-guided tissue regeneration in the healing course of segmental bone defects and study the mechanism. METHODS Segmental, 1 cm osteoperiosteal defects were produced in both radii of 12 rabbits. One side was covered with hydroxyapatite/polylactic acid(HA/PLA) membrane encapsulated as a tube. The contralateral side served as an untreated control. Healing courses were detected by radiographic and histologic examinations. RESULTS All control sides showed nonunion, whereas there were consistent healing pattern in test sides. CONCLUSION Membrane technique can promote bone regeneration.
Objective To evaluate the effects of surgical treatment for severe ocular rupture with blood staining of cornea and non-light perception , and analyze the relative factors. Methods Seven severely rup tured eyes of 7 patients with blood staining of cornea and non-light perception underwent second-stage penetrating keratoplasty combined with vitrectomy using temporary keratoprosthesis. All injured eyes had blood staining of cornea, hemorrhage in anterior chamber and vitreous, and choroidal and retinal detachment before the second-stage surgery. The average interval of the two surgical stages was 18 days (12-21 days). The preoperative visual acuity was non-light percept ion in all injured eyes with the mean intraocular pressure of 3 mm Hg (1 mm Hg =0.133 kPa) (2-5 mm Hg).The mean follow-up period was 12 months (6-30 months). Results The postoperative visual acuity was better than light perception in 5 eyes with the best corrected visual acuity of light perception to 0.06. The retina was attached in 5 eyes (5/7). The mean postoperative intraocular pressure was 12 mm Hg(5-15 mm Hg)which was significantly higher than the preoperative one (Plt;0.05). Postoperative complications mainly included temporary intraocular hypertension (1 eye), corneal neovasculariza tion (4 eyes), cornea rejection (4 eyes), and ocular atrophy (2 eyes). Conclusion Penetrating keratoplasty combined with vitrectomy using temporary keratoprosthesis is a safe and effective method in treating severe ocular rupture with blood staining of cornea and non-light perception. (Chin J Ocul Fundus Dis，2004，20：212-214)
Objective To evaluate the effect of internal fixation on the stability of pedicled fascial flap and the osteogenesis of exceed critical size defect (ECSD) of bone so as to provide theory for the clinical application by the radiography and histology observation. Methods The ECSD model of the right ulnar midshaft bone and periosteum defect of 1 cm in length was established in 32 New Zealand white rabbits (aged 4-5 months), which were divided into group A and group B randomly (16 rabbits in each group). The composite tissue engineered bone was prepared by seeding autologous red bone marrow (ARBM) on osteoinductive absorbing material (OAM) containing bone morphogenetic protein and was used repair bone defect. A pedicled fascial flap being close to the bone defect area was prepared to wrap the bone defect in group A (control group). Titanium miniplate internal fixation was used after defect was repair with composite tissue engineered bone and pedicled fascial flap in group B (experimental group). At 2, 4, 6, and 8 weeks, the X-ray films examination, morphology observation, and histology examination were performed; and the imaging 4-score scoring method and the bone morphometry analysis was carried out. Results All rabbits survived at the end of experiment. By X-ray film observation, group B was superior to group A in the bone texture, the space between the bone ends, the radiographic changes of material absorption and degradation, osteogenesis, diaphysis structure formation, medullary cavity recanalization. The radiographic scores of group B were significantly higher than those of group A at different time points after operation (P lt; 0.05). By morphology and histology observation, group B was superior to group A in fascial flap stability, tissue engineered bone absorption and substitution rate, external callus formation, the quantity and distribution area of new cartilage cells and mature bone cells, and bone formation such as bone trabecula construction, mature lamellar bone formation, and marrow cavity recanalization. The quantitative ratio of bone morphometry analysis in the repair area of group B were significantly larger than those of group A at different time points after operation (P lt; 0.05). Conclusion The stability of the membrane structure and the bone defect area can be improved after the internal fixation, which can accelerate bone regeneration rate of the tissue engineered bone, shorten period of bone defect repair, and improve the bone quality.
OBJECTIVE To sum up the experience of diagnosis and treatment of intrinsic upper gastro-intestinal membrane, 13 cases in children were studied retrospectively. METHODS There were 10 boys and 3 girls, the major symptoms were vomiting and epigastric distension. Eleven cases were treated by membranectomy with intestinal plasty, and 2 cases were treated by retrocolic side to end duodenojejunostomy. RESULTS All cases had good results without severe complications. CONCLUSION The children who have typical symptom of upper digestive tract should be considered duodental and upper jejunal membrane, and should be proved by contrast radiology. The membranectomy with intestinal plasty is the better operative method.
Objective To investigate the effect of repairing bone defect with tissue engineered bone seeded with the autologous red bone marrow (ARBM) and wrapped by the pedicled fascial flap and provide experimental foundation for cl inicalappl ication. Methods Thirty-two New Zealand white rabbits (male and/or female) aged 4-5 months old and weighing2.0-2.5 kg were used to make the experimental model of bilateral 2 cm defect of the long bone and the periosteum in the radius. The tissue engineered bone was prepared by seeding the ARBM obtained from the rabbits on the osteoinductive absorbing material containing BMP. The left side of the experimental model underwent the implantation of autologous tissue engineered bone serving as the control group (group A). While the right side was designed as the experimental group (group B), one 5 cm × 3 cm fascial flap pedicled on the nameless blood vessel along with its capillary network adjacent to the bone defect was prepared using microsurgical technology, and the autologous tissue engineered bone wrapped by the fascial flap was used to fill the bone defect. At 4, 8, 12, and 16 weeks after operation, X-ray exam, absorbance (A) value test, gross morphology and histology observation, morphology quantitative analysis of bone in the reparative area, vascular image analysis on the boundary area were conducted. Results X-ray films, gross morphology observation, and histology observation: group B was superior to group A in terms of the growth of blood vessel into the implant, the quantity and the speed of the bone trabecula and the cartilage tissue formation, the development of mature bone structure, the remolding of shaft structure, the reopen of marrow cavity, and the absorbance and degradation of the implant. A value: there was significant difference between two groups 8, 12, and 16 weeks after operation (P lt; 0.05), and there were significant differences among those three time points in groups A and B (P lt; 0.05). For the ratio of neonatal trabecula area to the total reparative area, there were significant differences between two groups 4, 8, 12, and 16 weeks after operation (P lt; 0.05), and there were significant differences among those four time points in group B (P lt; 0.05).For the vascular regenerative area in per unit area of the junctional zone, group B was superior to group A 4, 8, 12, and 16 weeks after operation (P lt; 0.05). Conclusion Tissue engineered bone, seeded with the ARBM and wrapped by the pedicled fascial flap, has a sound reparative effect on bone defect due to its dual role of constructing vascularization and inducing membrane guided tissue regeneration.
Idiopathic macular membrane (iERM) is a fibrocellular membrane that forms on the inner surface of the retina. In its early stages, symptoms of iERM are usually not apparent. However, advanced iERM can cause different degrees of visual impairment and effect the quality of life of patients. Current studies suggest that iERM may be associated with posterior vitreous detachment (PVD), age, sex, race and/or ethnicity, poor lifestyle, refractive error, diabetes, hypercholesterolemia, and cardiovascular disease. The most well-established risk factors for iERM are age and PVD. The pathogenesis of iERM is extremely complex. Various cell types, such as Müller cells, Hyalocytes and myofibroblasts, nerve growth factor, interleukin-6, transforming growth factor β, vascular endothelial growth factor and other cytokines and growth factors, as well as a variety of genes and proteins are directly or indirectly involved in the formation of iERM, however, their exact role remains a mystery. In the future, further studies at the molecular level and gene level are needed to provide greater help for the clinical diagnosis and treatment of iERM.
Objective To study the responsiveness change of neutrophils when experiencing the second insult after the initial temperature activation in cardiopulmonary bypass (CPB) by using an in vitro model. Methods The neutrophils were isolated from blood which was drawn from each of 60 health volunteers. The samples were divided into 5 groups including normothermia, tepid temperature, moderate hypothermia, deep hypothermia, and rewarming hyperthermia by random digital table with 12 in each group according to the change of temperature during CPB. An in vitro model for studying neutrophil responsiveness was established by using a polymerase chain reaction thermocycler. Five time points were set for each group, including T0: starting CPB, T1: starting rewarming, T2: 0.5 h after rewarming, T3: 1 h after rewarming, and T4: 1.5 h after rewarming. Platelet activating factor (PAF) was added into each group at T2, T3, and T4, and then the value of membranebound elastase (MBE) activity was measured as responsiveness of neutrophils. Analysis of covariance was applied by using SPSS 13.0 for statistic analysis. If the [CM(159mm]covariance had significant difference between main effects, Bonferroni method would be applied for pairwise comparison. Results The main effect difference of neutrophil responsiveness among different groups was statistically different (F=4.372,P=0.002). MBE value had no statistical difference between the normothermia and tepid temperature groups (81.9±4.5 ng/10.6 cells vs. 76.5±3.6 ng/106 cells, P=0.134). while the MBE values in these two groups were higher than those in the other three groups (P=0.001). MBE value in the rewarming hyperthermia group was higher than that in the deep hypothermia group (61.2±2.7 ng/106 cells vs. 50.9±3.7 ng/106 cells, P=0.005). There was no statistical difference between the moderate hypothermia group (56.4±3.2 ng/106 cells) and the rewarming hyperthermia group (P=0.167), so was it between the moderate hypothermia group and the deep hypothermia group (P=0.107). The main effects of neutrophil responsiveness at different time points was statistically different (F=3.566, P=0.03) when PAF was added. MBE value at T4 was higher thanthat at T2 (70.9±2.5 ng/106 cells vs. 59.9±2.3 ng/106 cells, P=0.027). There was no statistical difference among T3 (65.5±1.8 ng/106 cells), T2 (P=0.168), and T4 (P=0.292) in MBE value. Conclusion Normothermia， tepid temperature， and rewarming hyperthermia during CPB can enhance neutrophil responsiveness and MBE release when neutrophils suffer the second insult. There is a time window for neutrophils to be easily activated during rewarming period.
Objective To compare the effect between vascularization osteogenesis and membrane guided osteogenesis in the bone repair by the tissue engineered bone with pedicled fascial flap packing autologous red bone marrow (ARBM), so as to provide a reference for the bone defect repair in cl inic. Methods The tissue engineered bone was constructed with ARBM and the osteoinductive absorbing recombinant human materials with recombinant human bone morphogenetic protein 2. Sixty New Zealand rabbits (aged 4-5 months, weighing 2.0-2.5 kg) were randomly divided into group A (n=16), group B (n=22), and group C (n=22). The complete periosteum defect model of 1.5 cm in length was prepared in right ulnar bone, then the tissue engineered bone was implanted in the bone defect area in group A, the tissue engineered bonewith free fascial flap in group B, and the tissue engineered bone with pedicled fascial flap in group C. At 4, 8, 12, and 16 weeks, the tissue of bone defect area was harvested from 4 rabbits of each group for the general, histological, and immunohistochemical staining observations; at 8, 12, and 16 weeks, 2 rabbits of groups B and C, respectively were selected to perform ink perfusion experiment by axillary artery. Results The general observation showed that the periosteum-l ike tissues formed in the fascial flap of groups B and C, chondroid tissues formed in group B, new bone formed in group C, and the fibrous and connective tissues in group A at 4 and 8 weeks; a few porosis was seen in group A, more new bone in group B, and bone stump formation in group C at 12 and 16 weeks. Histological observation showed that there were few new blood vessels and new bone trabeculae in groups A and B, while there were large amounts of new blood vessels and mature bone trabeculae in group C at 4 and 8 weeks. There were a few new blood vessels and new bone trabeculae in group A; more blood vessels, significantly increased mature trabeculae, and the medullary cavity formation in group B; and gradually decreased blood vessels, the mature bone structure formation, and the re-opened medullary cavity in group C at 12 and 16 weeks. The immunohistochemical staining observation showed that the levels of CD105, CD34, and factor VIII were higher in group C than in groups A and B at different time points.The bone morphometry analysis showed that the trabecular volume increased gradually with time in 3 groups after operation; the trabecular volume in group C was significantly more than those in groups A and B at different time points (P lt; 0.05); and there was significant difference between groups A and B (P lt; 0.05) except the volume at 4 weeks (P gt; 0.05). The vascular image analysis showed that the vascular regenerative area ratio in group C was significantly higher than those in groups A and B at different time points (P lt; 0.05). The ink perfusion experiment showed that the osteogenic zone had sparse ink area with no obvious change in group B, while the osteogenic zone had more intensive ink area and reached the peak at 8 weeks, then decreased in group C. Conclusion The tissue engineered bone with pedicled fascial flap packing ARBM has the vascularization osteogenesis effect at early stage, but the effect disappears at late stage gradually when the membrane guided osteogenesis is main.
Objective To observe the influences of depolarized arrest and hyperpolarized arrest on alternation of fluidity of myocardial cell membrane during cardiopulmonary bypass (CPB) and evaluate the protective effects on myocardium of hyperpolarized arrest. Methods Seventy-two felines were randomized into three groups, each group 24. Control group: 180 minutes of CPB was conducted without aortic and vena caval cross-clamping. Depolarized arrest group: hearts underwent 60 minutes of global ischemia after aortic cross-clamping (ACC) followed by 90 minutes of reperfusion. The cardioplegic solution consisted of St. Thomas solution (K+16mmol/L). Hyperpolarized arrest group: the protocol was the same as that in depolarized arrest group except that the cardioplegic solution consisted of St.Thomas solution with pinacidil (50 mmol/L,K+5mmol/L). Microviscosity, the reciprocal of fluidity of myocardial membrane was measured in all groups by using fluorescence polarization technique. (Results )Microvis cosity of myocardial cell in depolarized arrest group during ACC period was significantly higher than that before ACC and kept on rising during reperfusion period. Microviscosity of myocardial cell in hyperpolarized arrest group during ACC was trending up and reperfusion periods as well, but markedly lower compared to that in depolarized arrest group at corresponding time points(Plt;0.01). Conclusion Hyperpolarized arrest is more effective in protecting myocardial cells from ischemia-reperfusion injury than depolarized arrest during CPB by maintaining better fluidity of myocardial membrane.
In this paper,the results of vitreous surgery in 25 cases of PVR D3 were analyzed.Pars plana vitrectomy and membrane peeling were performed in all eyes.The follow-up is more than 3 months.The anatomic successful rate was 68%.The authors suggest that vitrectomy combined with membrane peeling and intraocular tamponade was key for the treatment of PVR D3.Silicone oil tamponade may improve the patients'prognosis.The authors suggest that the etiologic factors may include the operative irritation,giant tear,trauma and vitreous hemorrhage.The time and the complications of the vitreous surgery were discussed. （Chin J Ocul Fundus Dis,1993,9:145-147）